(1) Field of the Invention
The present invention relates to a self-propelled machine for laying a catenary and/or a contact wire of an overhead line extending above a track and attached to pylons spaced alongside the track, which comprises a machine frame having two opposite ends, undercarriages supporting the machine frame at the ends thereof for mobility on the track, a drive for moving the machine frame along the track in an operating direction, a driving operator's cab mounted on the machine frame, a power-driven, vertically adjustable work platform mounted on the machine frame for an operator assigned to attaching the overhead line to the pylons, a storage drum mounted on the machine frame, a length of the catenary and/or contact wire being reeled on the storage drum and the drum being rotatable at a pay-out speed for unreeling the catenary and/or contact wire, a drive control for adjusting the moving speed of the machine frame in response to the pay-out speed of the catenary and/or contact wire, a lifting device mounted on the machine frame, the lifting device including a power-driven, vertically adjustable and laterally pivotal boom and a support and guide pulley carried by the boom and arranged to support and guide the unreeled catenary and/or contact wire from the storage drum to the operator on the work platform, and a controllable device for tensioning the catenary and/or contact wire, which includes a guide roller.
(2) Description of the Prior Art
German patent No. 2,211,247, published Feb. 19, 1981, cites pages 214 to 226 of "Fahrleitungsnetz" by I. I. Wlassow, published in 1955 by Fachbuchverlag Leipzig, as state of the art. This publication discloses laying an overhead line comprised of a catenary and contact wire above a track by first affixing one end of the catenary and then guiding it over rollers mounted at spaced locations. For this purpose, use is made of a mobile car running on the track and carrying a rotatable storage drum for the catenary, and a brake is provided for the drum. After a section of the catenary has been laid, the catenary is tensioned or stretched by a tackle and the free end of the stretched catenary is permanently fixed in position. Subsequently, hangers are attached to the catenary and the contact wire is laid in the same manner and is suspended from the catenary by temporary hangers. The contact wire is then tensioned or stretched by one or more tackles and is fixed, whereupon it is attached to the permanent hangers. Laying an overhead line in this manner requires considerable work. Paying out or reeling the catenary and the contact wire on the storage drums is relatively difficult because they do not extend parallel to the track but in a zig-zag formation from one side of the track to the opposite side where the overhead line is affixed to spaced pylons at the track shoulders. It is, therefore, very time-consuming to obtain a proper pay-out of the catenary and the contact wire from the drum to its final position.
"Japanese Railway Engineering", Vol. 9, 1968, pages 23-25, discloses a catenary inspection and catenary stretching car for the inspection and simple repair of an overhead line. The car carries rotatable storage drums for the contact wire. When the contact wire is extended, the drum is braked by an oil pressure brake so that the contact wire ma be laid while tensioned. The car is not used for laying a new overhead line comprised of a catenary and a contact wire but only to replace a worn contact wire by a new contact wire on a catenary and hangers which are already in place. A rapid and accurate laying of the contact wire and/or the catenary is not possible with this car because of their zig-zag extension which is not parallel to the track.
German patent No. 526,889, published June 11, 1931, discloses a mobile car running on a track for laying an electrical overhead line above the track. Several wire storage drums are mounted on the car which also carries a lifting arm for raising the wires reeled off the drums to the level of hooks above the track, to which the wires are attached. This arrangement makes it possible to lay several wires simultaneously but these wires are not connected to each other. An accurate pay-out of the wires from the drum encounters the above-described difficulties because they wires do not extend parallel to the track.
The above-cited German patent No. 2,211,247 discloses a machine of the first-described type for the temporary installation of an overhead line. The self-propelled car of this machine carries the following structures: drums for storing the catenary cable and the contact wire and for paying them out under a controlled tension; a hook-sensing device; a tensioning device control with a drive for imparting a longitudinally extending tensioning force; a device for delivering the wire hangers; a suspension device operating in response to a sensing signal for suspending the catenary in the hooks; and an anchoring device for the other end of the catenary and/or the contact wire. A lifting arm, which is vertically adjustable by a power drive, is mounted between the drums and an upper portion of the contact wire and catenary and a carrier arm for two relatively small-diameter guide pulleys spaced from each other in the longitudinal extension of the machine frame lift and support the contact wire and the catenary, and a similarly small-diameter guide roller guides them over the tensioning device to the drums. This machine construction is of a relatively complex design and still is useful only for the temporary or provisional installation of the contact wire and catenary under tension. It, too, makes an accurate pay-out of the contact wire and the catenary from the drums as well as guidance over the tensioning device and guide rollers difficult, if not impossible, because in its final and permanent position, they extend in a zig-zag formation. Furthermore, the distance between the lifting device and the storage drums is relatively large in the longitudinal extension of the machine frame, which requires long connection wires for affixing the ends of the contact wire and/or catenary to the pylons. In particular, the machine requires an expensive and complex hook-sensing device as well as a device for delivering temporary hangers in connection with the wire-suspension device to make it possible at least approximately to guide the vertically and laterally adjustable carrier arm equipped with guide pulleys on the vertically adjustable work platform so that it can follow the alternating change in direction of the catenary and/or contact wire as it extends from pylon to pylon on the opposite track shoulders--and even this only provisionally. The suspension of the tensioned catenary is effected by the two spaced guide pulleys which are lifted with the carrier arm and the catenary section extending between the pulleys is suspended on the temporary hook therebetween. This provisional installation is very uneconomical and time-consuming, and the temporary hangers must be removed after the provisional installation in a subsequent operation to enable the permanent attachment elements to be mounted during a subsequent tensioning and orienting operation.